1. Field of the Invention
The invention relates to a method for starting the internal combustion engine of a hybrid vehicle and to a hybrid vehicle that controls the starting process of an internal combustion engine.
2. Description of the Related Art
Hybrid vehicles are generally understood to be a vehicle that is driven by at least one internal combustion engine and one or more electric drive motors. In this context, for example when the vehicle starts or at low velocities or accelerator pedal positions, the vehicle is driven solely by the electric drive motor, while at relatively high velocities or accelerator pedal positions the internal combustion engine assumes the driving of the hybrid vehicle together with the electric drive motor. It is also possible that the hybrid vehicle is moved solely by the internal combustion engine, for example if the battery provided for operating the electric drive motor no longer has any stored electrical energy.
These various types of drive make it necessary to start the internal combustion engine while the hybrid vehicle is travelling to assist the electric drive of the vehicle.
EP 1 489 294 A2 relates to a start/stop system having a motor generator and a separate control motor for starting an internal combustion engine. In this context, a temperature monitor is provided and re-starting the internal combustion engine by the starter is provided in a timed fashion to prevent overheating the motor generator.
DE 10 2007 012 046 A1 presents a hybrid vehicle with an electric motor and a separate starter for starting an internal combustion engine. An abnormality detector prevents the internal combustion engine from being started by the electric motor.
FR 2 928 122 proposes determining the optimum operating time of a hybrid drive train as a function of the position of the accelerator pedal.
US 2009/0112383 A1 discloses an electric vehicle in which the user can switch on a desired driving mode.
According to US 2009/0287366 A1, starting the internal combustion engine is prevented when an electric driving mode of a hybrid vehicle is selected manually.
The object of the invention is to improve the starting process of the internal combustion engine and to be able to make available a starting process that is more appropriate for the situation.